US4593262A - Time delay indicator fuse - Google Patents
Time delay indicator fuse Download PDFInfo
- Publication number
- US4593262A US4593262A US06/715,097 US71509785A US4593262A US 4593262 A US4593262 A US 4593262A US 71509785 A US71509785 A US 71509785A US 4593262 A US4593262 A US 4593262A
- Authority
- US
- United States
- Prior art keywords
- fuse
- spring
- junction
- resistor
- terminal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H85/00—Protective devices in which the current flows through a part of fusible material and this current is interrupted by displacement of the fusible material when this current becomes excessive
- H01H85/02—Details
- H01H85/36—Means for applying mechanical tension to fusible member
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H85/00—Protective devices in which the current flows through a part of fusible material and this current is interrupted by displacement of the fusible material when this current becomes excessive
- H01H85/02—Details
- H01H85/30—Means for indicating condition of fuse structurally associated with the fuse
- H01H85/303—Movable indicating elements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H85/00—Protective devices in which the current flows through a part of fusible material and this current is interrupted by displacement of the fusible material when this current becomes excessive
- H01H85/0039—Means for influencing the rupture process of the fusible element
- H01H85/0047—Heating means
- H01H85/0052—Fusible element and series heating means or series heat dams
Definitions
- This invention has two important applications, the first in slow blowing, tubular fuses of the type having a spring, a heat sink, and a thin fusible element, and which are particularly well suited for protecting electric motor starting circuits.
- Such fuses are designed to break an electrical circuit after either a predetermined interval under a sustained modest overload, or almost immediately under a given high overload, as, for example, under short circuit, high energy, arc-producing conditions.
- This first application of the present invention relates to a unique fuse construction and arrangement for removing the inherent stress upon the thin, fragile fusible element within such prior art fuses so as to avoid breakage of the element when such fuses are either dropped or subjected to external vibration forces.
- the second important application pertains to an indicator unit that may be placed in parallel with a fuse of virtually any construction so as to provide a blown fuse indication upon the blowing of the existing fuse.
- the indicator is generally similar in construction to the fuse described above, but does not include the thin fusible element.
- Tubular fuses for protecting electrical circuits are well-known and generally include a cylindrical insulating housing made, for example, of glass. The opposite axial ends of the cylindrical housing are closed by a pair of generally cup-shaped fuse end terminals. A globule of molten solder is typically placed within each of the fuse terminals just prior to their assembly with the housing. As the solder cools, it solidifies so as to secure the fuse terminals to the outer wall surface at the ends of the housing. The solidified solder also supports serially-located elements disposed within the fuse housing and providing electrical continuity through the fuse between the fuse terminals.
- Certain prior art slow blowing fuses of this general type include a tensed metal coil spring having one of its ends secured to one of the fuse terminals, and its other end connected through a heat meltable joint to the coiled end portion of a fuse wire.
- the other end portion of the fuse wire is straight and extends to the opposite fuse terminal.
- the coiled portion of the fuse wire is wound around a heat sink-forming core of ceramic or other insulating material which is in physical contact with the meltable joint.
- the spring and/or a shunt-forming conductor connected across the ends of the spring provides electrical continuity between the fuse wire and the former terminal.
- the coil spring is held in its expanded tensed condition by the meltable joint and it imparts tension upon the fuse wire.
- the heat generated by current flow through the coiled portion of the fuse wire wound around the core heats the core to a point where the meltable joint in contact therewith melts or softens sufficiently that the spring pulls away from the meltable joint and collapses towards the adjacent, former fuse terminal.
- the spring is connected to and surrounds an axially-extending indicator pin which is normally fully retracted within the fuse housing. The collapse of the spring pulls the shunt-forming conductor and indicator pin away from the fuse wire to open the protective circuit, and moves the indicator pin through a hole in the former fuse terminal where it projects from the housing so as to indicate a blown fuse condition.
- the mid-section of the straight portion of the fuse wire melts or vaporizes and the coil spring then collapses and pulls the coiled portion of the fuse wire away from the opposite end of the fuse housing, to fully open the circuit involved and prevent the formation of a sustained arc at the point where the fuse wire had melted.
- the spring tension on the fuse wire does not give rise to problems if the fuse wire is of a substantial diameter, as it usually is in high current rated fuses.
- low current rated fuses frequently have thin, fragile fuse wire, and the spring tension applied thereto sometimes causes the fuse wire to break, permanently damaging the fuse, when dropped or subjected to external vibration forces.
- Another aspect of the invention enables the retrofit of indicator fuses to existing fuse-protected circuits. These existing circuits will typically not have fuses with integral indicators, and the present indicator fuses will, when placed in parallel with the existing fuses, provide them with a blown fuse indication.
- the need to place spring tension on the fuse wire for a quick separation under short circuit conditions of the fuse element parts as just described is eliminated by designing the fuse to open under short circuit conditions in a two step manner.
- the ceramic insulator previously described is replaced by a resistor, such as a carbon resistor, having an insulating body around which the coiled portion of the fuse wire is wound.
- the resistor body acts as a heat sink and is in contact, along with the short stub of the adjacent resistor terminal lead, with the spring-connected meltable joint.
- the other terminal lead of the resistor and the straight, end portion of the fuse wire are secured to the adjacent fuse terminal at the end of the fuse housing, and this terminal, through the resistor's other terminal lead, takes the spring tension imparted by the spring.
- the fuse wire is connected in parallel across the resistor terminal leads such that there is no tension from the coil spring upon the fuse wire.
- the resistance value of the resistor is many times the resistance of the coiled heater-forming portion of the fuse wire so that when the fuse is in an intact, unblown state, practically all of the current flowing through the fuse flows through the fuse wire.
- the overload current heats the coiled portion of the fuse wire which, in turn, heats the resistor body.
- the meltable joint adjacent thereto melts.
- the coil spring which is mechanically connected to the resistor body and fuse wire through the meltable joint, collapses away from the resistor and fuse wire, to interrupt electrical continuity within the fuse, as in the prior art fuse previously described.
- the straight portion of the fuse wire melts or vaporizes abruptly.
- the resistor in parallel with the heating coil, still provides a path through which current may flow.
- the resistor body heats up in a very short time and causes a rapid melting of the adjacent meltable joint while the coil spring collapses and opens the entire fuse, as described above.
- the fuse may include an indicator pin as described, movable from a retracted position within the fuse housing to an extended position, thereby providing a blown fuse indication for the prolonged overload and short circuit conditions.
- an indicator unit of a construction substantially similar to that of the two-step fuse described hereinabove is provided.
- the indicator unit differs from the two-step fuse in that it does not include the fuse wire that is connected in parallel across the resistor terminal leads.
- the indicator unit is placed in parallel with a second fuse.
- the fuse is of a substantially lower resistance than that of the indicator unit, so that most of the current flowing through the protected circuit passes through the fuse.
- the relatively high resistance of the indicator unit reduces current flow through the protected circuit.
- the current which then flows through the indicator unit causes it to operate in a manner that is virtually identical to that of the above-described two-step fuse after short-circuit conditions have evaporated or melted the fuse wire.
- the resistor body of the indicator unit heats up in a very short time and causes a rapid melting of its adjacent meltable joint.
- the coil spring then collapses, which opens the circuit path through the indicator unit.
- the indicator pin thus moves to its extended position to provide a blown fuse indication for the separate blown fuse.
- FIG. 1 is a perspective view of a preferred form of the slow blow fuse of the invention
- FIG. 2 is a longitudinal sectional view through the fuse of FIG. 1;
- FIG. 3 is a view of the fuse of FIG. 2 after the fuse has blown due to prolonged, moderate overload current conditions
- FIG. 4 is a longitudinal sectional view of the fuse of FIG. 2 after blowing due to sudden, high overload or short circuiting conditions;
- FIG. 5 is a schematic perspective view of the indicator unit of the present invention in parallel with a separate fuse
- FIG. 6 is a longitudinal sectional view of the indicator unit of FIG. 5, showing the indicator unit in an intact, unblown state.
- the fuse comprises a housing in the form of a tube 14 of insulating material such as transparent glass and having an inner wall surface 16 and an outer wall surface 18 and two opposite axial ends 20 and 22.
- a first cup-shaped metal fuse terminal 24 is secured to axial end 20 and a second cup-shaped metal fuse terminal 26 is secured in a like manner to opposite axial end 22.
- the fuse includes serially-located elements 28 disposed within the fuse housing and providing electrical continuity between the first fuse terminal 24 and the second fuse terminal 26.
- the elements comprise an elongated, stressed spring 30 and a resistor 32 having an insulating outer housing or body 32a, the spring and resistor being mechanically and electrically secured to each other at a meltable joint or junction 34.
- the stressed spring 30 is preferably conical and is tapered inwardly from relatively wide turns 36 adjacent the first fuse terminal 24 to relatively narrow turns 38 adjacent to the meltable junction 34.
- the proximate end 40 of the spring 30 is mechanically and electrically secured to the first fuse terminal 24.
- a solder globule 42 is placed in the first fuse terminal 24, and the terminal 24 is then secured over the axial end 20 of tube 14 so that the end wall 24a of the terminal 24 traps the widest and endmost turn of the spring 30 between the terminal end wall 24a and the tube end 20. Cooling of the solder globule results in a good mechanical and electrical connection between the fuse terminal, housing, and spring.
- the other end of the spring is secured with the spring under tension to the meltable junction 34 along with one end of a metal shunt-forming strap or wire 44.
- the other end of the metal strap 44 is preferably placed in the gap between the cylindrical wall 24b of the terminal 24 and the tube 14, into which gap some of the solder 42 is drawn by capillary action.
- the resistor body 32a is in contact with the meltable juntion.
- the resistor 32 can be of any suitable electrically conducting material. Its resistance may be, for example, 250 ohms.
- One terminal lead 32b of the resistor is mechanically secured to the spring 30 through the meltable junction 34.
- the other terminal lead 48 of the resistor is electrically connected to the second fuse terminal 26 through a solder globule 46 securing the second fuse terminal 26 to the axial end 22 of the tube 14. It will be appreciated that in this manner the tension imparted by the stressed conical spring 30 to the meltable junction 34 and the rest of the assembly thus far described is entirely taken up by the resistor 32 and the meltable junction 34.
- the meltable junction 34 may comprise a globule of solder or other suitable substance which is solid at the normal operating temperatures of fuses, and capable of providing a solid mechanical and a good, low resistance electrical connection between the resistor and the spring.
- the shunt wire 44 provides a low resistance shunt between the first fuse terminal 24 and the meltable junction 34, so that spring 30 need not be made of very low resistance conductive material.
- the resistor body 32a is surrounded by the coiled portion 50a of a fuse wire 50 having a straight portion 50b.
- the fuse wire is loosely, that is with only modest tension, connected across the resistor leads so that it takes none of the tension imparted by the spring 30.
- the coiled portion 50a of the fuse wire which is so low in resistance as compared to the resistance of resistor 32 that is carries practically all of the current flowing through the fuse, becomes appreciably heated. This heat is transferred to the resistor body 32a.
- the resistor body 32a reaches a temperature which melts the junction 34 so that the tensed spring 30 collapses to separate the spring from the resistor 32 and fuse wire 50 as shown in FIG. 3.
- the fuse wire 50 melts or vaporizes, whereupon the current in the circuit is transferred to the resistor 32 which heats up and melts the junction 34.
- the collapsing spring 41 pulls away from the resistor to open the fuse.
- the normal current i.e., current at 110% or less of the rated amperage of the fuse, passing through the coiled portion of the fuse wire is too small to create sufficient heat to melt meltable junction 34.
- the overload current heats the coiled portion 50a of the fuse wire 50 which, in turn, heats the resistor body 32a.
- the meltable joint 34 adjacent thereto melts.
- the coil spring 30, which is mechnically connected to the resistor body and fuse wire through the meltable joint, collapses away from the resistor and fuse wire, to interrupt electrical continuity within the fuse.
- the fuse may include an indicator pin 52 movable from a retracted position within the fuse as shown in FIG. 2 to an extended position, partially without the fuse, as shown in FIGS. 3 and 4.
- the indicator pin moves to its extended position upon the collapse of the coil spring 30 after the melting of the meltable junction.
- the indicator pin 52 is guidably mounted in an axially central aperture 54 in the end wall 24a of the first fuse terminal 24, and the terminal further includes a recessed portion 56 so that the head 58 of the indicator pin will be substantially flush with the rest of the exterior portion of end wall 24a when the fuse is in its normal unblown state.
- the distal end 60 of the indicator pin 52 is clampingly engaged by one of the narrow turns 38 of the stressed spring 30. When the spring collapses upon the melting of the meltable junction 34, each of the turns of the spring moves in the direction of the first fuse terminal 24. The turn clampingly engaging the distal end 60 of the indicator also necessarily moves towards the first fuse terminal 24 under such blown fuse conditions.
- the distal end of the indicator pin 52 is urged towards the first fuse terminal 24, and the head 58 of the indicator is moved away from the recessed portion 56 so that the pin 52 is in the extended position shown in either FIGS. 3 or 4.
- the indicator provides the user with a blown fuse indication.
- This aspect of the present invention provides all of the advantages of the prior art fuses and the additional advantage of durability in that it includes a fine fuse filament or heating coil element that is not under spring tension and is thus not as likely to break if the fuse is dropped or subjected to substantial vibration.
- the fuse is economical to manufacture and can be used in any environment where prior art slow blow fuses have been used.
- a second important aspect of this invention comprises an indicator unit 12' shown generally in FIG. 6 and shown in FIG. 5 in parallel with a separate fuse 62 so as to provide an indication of a blown fuse condition for the fuse, as will be explained hereinbelow.
- the indicator unit is substantially identical to the fuse of FIG. 2, except that it does not have the fuse wire 50.
- the unit comprises a housing in the form of a tube 14' of insulating material, such as transparent glass, and having an inner wall surface 16' and an outer wall surface 18' and two opposite axial ends 20' and 22'.
- a first cup-shaped metal terminal 24' is secured to axial end 20' and a second cup-shaped metal terminal 26' is secured in a like manner to opposite axial end 22'.
- the indicator unit includes serially-located elements disposed within the housing thereof and providing electrical continuity between the first terminal 24' and the second terminal 26'.
- the elements comprise an elongated stressed spring 30' and a resistor 32' having an insulating outer housing or body 32a', the spring and resistor being mechanically and electrically secured to each other at a meltable joint or junction 34'.
- One end of a metal shunt-forming strap or wire 44' is also anchored to the meltable junction 34'.
- the other end of the metal strap 44' is placed in the gap between the cylindrical wall 24b' of the terminal 24' and the tube 14'.
- the indicator unit also includes an indicator pin 52' movable from a retracted position within the fuse as shown in FIG. 5 to an extended position, partially outside of the unit, as exemplified by the two-step fuse in its blown condition in FIGS. 3 and 4.
- the indicator pin moves to its extended position upon the collapse of the coil spring after the melting of the meltable junction.
- the operation of the indicator unit is as follows. Because the resistance of the indicator unit 12' is designed to be substantially higher than that of the fuse 62 through the inclusion of a suitably high-resistance resistor 32', under normal operating conditions most of the current passing through the protected circuit of FIG. 5 passes through fuse 62. Upon sudden, short circuiting conditions or under prolonged, steady overload conditions, the fuse 62 blows in accordance with its design characteristics. At this point, a very small current passing through the protected circuit can only pass through indicator unit 12'. The magnitude of this current will cause resistor 32' to heat, melting the meltable junction. The mechanical connection of the resistor with the spring will have thereby become destroyed, causing collapse of the spring and interrupted electrical contact. Under these conditions, the end 38' of the spring 30' clampingly engaging the indicator pin 52' will urge the pin into the partially extended position so as to provide the circuit with a blown fuse indication.
- the coiled portion 30a could, in accordance with the broadest aspect of the invention, be replaced by a resistor of much lower value than the load resistance of the circuit involved. This resistor is placed next to the resistor body 32a or junction 34 to melt the junction upon such a prolonged modest overload.
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Abstract
Description
Claims (9)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/715,097 US4593262A (en) | 1985-03-22 | 1985-03-22 | Time delay indicator fuse |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/715,097 US4593262A (en) | 1985-03-22 | 1985-03-22 | Time delay indicator fuse |
Publications (1)
Publication Number | Publication Date |
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US4593262A true US4593262A (en) | 1986-06-03 |
Family
ID=24872662
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/715,097 Expired - Lifetime US4593262A (en) | 1985-03-22 | 1985-03-22 | Time delay indicator fuse |
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US (1) | US4593262A (en) |
Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5187463A (en) * | 1992-02-11 | 1993-02-16 | Gould, Inc. | Compact time delay fuse |
US5254967A (en) | 1992-10-02 | 1993-10-19 | Nor-Am Electrical Limited | Dual element fuse |
US5355110A (en) | 1992-10-02 | 1994-10-11 | Nor-Am Electrical Limited | Dual element fuse |
US5406244A (en) * | 1994-01-25 | 1995-04-11 | Gould Electronics Inc. | Time delay fuse |
US5418515A (en) * | 1993-12-22 | 1995-05-23 | Reyes; Daniel | Fuse interruption indicator and integral extractor |
US5831507A (en) * | 1996-09-09 | 1998-11-03 | Toyo System Co., Ltd. | Dual-functional fuse unit that is responsive to electric current and ambient temperature |
US6204747B1 (en) * | 1997-11-21 | 2001-03-20 | James L. Kitchens | Safety devices for electrical circuits and systems |
US6256183B1 (en) | 1999-09-09 | 2001-07-03 | Ferraz Shawmut Inc. | Time delay fuse with mechanical overload device and indicator actuator |
US6538551B2 (en) * | 2001-08-22 | 2003-03-25 | Cooper Technologies Company | Heat concentrating barrel for wire heater in dual element fuses |
US6603385B2 (en) | 1997-11-21 | 2003-08-05 | Safety Thermal Components, Inc. | Safety devices for electrical circuits and systems |
US20030179069A1 (en) * | 2002-03-02 | 2003-09-25 | Borchardt Glenn R. | High voltage fuse |
US20060214762A1 (en) * | 2005-03-24 | 2006-09-28 | Rogers Jonathan P | Dual fuse holder |
US20070046418A1 (en) * | 2005-08-30 | 2007-03-01 | Eaton Corporation | Electrical distribution device including protection for overheating conditions |
DE102006034404A1 (en) * | 2006-06-08 | 2007-12-13 | Dehn + Söhne Gmbh + Co. Kg | Overcurrent protection device for use in surge protection devices with additional mechanical release, preferably designed as a firing pin |
US20080117015A1 (en) * | 2006-11-22 | 2008-05-22 | Thomas & Betts International, Inc. | Fuse providing circuit isolation and visual interruption indication |
US20080297301A1 (en) * | 2007-06-04 | 2008-12-04 | Littelfuse, Inc. | High voltage fuse |
US20100148913A1 (en) * | 2008-12-16 | 2010-06-17 | Wayne Hemmingway | Fuse element retaining device |
US20100245022A1 (en) * | 2009-03-24 | 2010-09-30 | Tyco Electronics Corporation | Electrically activated surface mount thermal fuse |
US20100245027A1 (en) * | 2009-03-24 | 2010-09-30 | Tyco Electronics Corporation | Reflowable thermal fuse |
US20130293343A1 (en) * | 2010-12-31 | 2013-11-07 | Xiamen Set Electronics Co., Ltd. | Device combining a thermal fuse and a resistor |
US8854784B2 (en) | 2010-10-29 | 2014-10-07 | Tyco Electronics Corporation | Integrated FET and reflowable thermal fuse switch device |
US20160042904A1 (en) * | 2014-08-08 | 2016-02-11 | Tyco Electronics France Sas | Smart Fuse for Circuit Protection |
US20160099125A1 (en) * | 2012-12-05 | 2016-04-07 | Eaton Corporation | Fuse with carbon fiber fusible element |
US9324533B2 (en) | 2013-03-14 | 2016-04-26 | Mersen Usa Newburyport-Ma, Llc | Medium voltage controllable fuse |
US9490096B2 (en) | 2013-03-14 | 2016-11-08 | Mersen Usa Newburyport-Ma, Llc | Medium voltage controllable fuse |
WO2018136317A1 (en) * | 2017-01-17 | 2018-07-26 | Littelfuse, Inc. | Fuse with conical open coil fusible element |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2111749A (en) * | 1933-06-19 | 1938-03-22 | Henry T Bussmann | Electric protective device |
US4058784A (en) * | 1976-02-23 | 1977-11-15 | Mcgraw-Edison Company | Indicator-equipped, dual-element fuse |
-
1985
- 1985-03-22 US US06/715,097 patent/US4593262A/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2111749A (en) * | 1933-06-19 | 1938-03-22 | Henry T Bussmann | Electric protective device |
US4058784A (en) * | 1976-02-23 | 1977-11-15 | Mcgraw-Edison Company | Indicator-equipped, dual-element fuse |
Cited By (38)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5187463A (en) * | 1992-02-11 | 1993-02-16 | Gould, Inc. | Compact time delay fuse |
US5254967A (en) | 1992-10-02 | 1993-10-19 | Nor-Am Electrical Limited | Dual element fuse |
US5355110A (en) | 1992-10-02 | 1994-10-11 | Nor-Am Electrical Limited | Dual element fuse |
US5418515A (en) * | 1993-12-22 | 1995-05-23 | Reyes; Daniel | Fuse interruption indicator and integral extractor |
US5406244A (en) * | 1994-01-25 | 1995-04-11 | Gould Electronics Inc. | Time delay fuse |
US5831507A (en) * | 1996-09-09 | 1998-11-03 | Toyo System Co., Ltd. | Dual-functional fuse unit that is responsive to electric current and ambient temperature |
US6603385B2 (en) | 1997-11-21 | 2003-08-05 | Safety Thermal Components, Inc. | Safety devices for electrical circuits and systems |
US6204747B1 (en) * | 1997-11-21 | 2001-03-20 | James L. Kitchens | Safety devices for electrical circuits and systems |
US6256183B1 (en) | 1999-09-09 | 2001-07-03 | Ferraz Shawmut Inc. | Time delay fuse with mechanical overload device and indicator actuator |
US6538551B2 (en) * | 2001-08-22 | 2003-03-25 | Cooper Technologies Company | Heat concentrating barrel for wire heater in dual element fuses |
US20030179069A1 (en) * | 2002-03-02 | 2003-09-25 | Borchardt Glenn R. | High voltage fuse |
US6720857B2 (en) * | 2002-03-02 | 2004-04-13 | S&C Electric Co. | High voltage fuse |
US20060214762A1 (en) * | 2005-03-24 | 2006-09-28 | Rogers Jonathan P | Dual fuse holder |
US7378933B2 (en) * | 2005-03-24 | 2008-05-27 | Jonathan Paige Rogers | Dual fuse holder |
US20070046418A1 (en) * | 2005-08-30 | 2007-03-01 | Eaton Corporation | Electrical distribution device including protection for overheating conditions |
US7400225B2 (en) * | 2005-08-30 | 2008-07-15 | Eaton Corporation | Electrical distribution device including protection for overheating conditions |
DE102006034404B4 (en) * | 2006-06-08 | 2014-05-28 | Dehn + Söhne Gmbh + Co. Kg | Overcurrent protection device for use with overvoltage arresters, with an additional mechanical release designed as a firing pin |
DE102006034404A1 (en) * | 2006-06-08 | 2007-12-13 | Dehn + Söhne Gmbh + Co. Kg | Overcurrent protection device for use in surge protection devices with additional mechanical release, preferably designed as a firing pin |
US7724122B2 (en) * | 2006-11-22 | 2010-05-25 | Thomas & Betts International, Inc. | Fuse providing circuit isolation and visual interruption indication |
US20080117015A1 (en) * | 2006-11-22 | 2008-05-22 | Thomas & Betts International, Inc. | Fuse providing circuit isolation and visual interruption indication |
US20080297301A1 (en) * | 2007-06-04 | 2008-12-04 | Littelfuse, Inc. | High voltage fuse |
US8169293B2 (en) * | 2008-12-16 | 2012-05-01 | Wayne Hemmingway | Fuse element retaining device |
US20100148913A1 (en) * | 2008-12-16 | 2010-06-17 | Wayne Hemmingway | Fuse element retaining device |
US20100245027A1 (en) * | 2009-03-24 | 2010-09-30 | Tyco Electronics Corporation | Reflowable thermal fuse |
US9343253B2 (en) | 2009-03-24 | 2016-05-17 | Tyco Electronics Corporation | Method of placing a thermal fuse on a panel |
US8289122B2 (en) | 2009-03-24 | 2012-10-16 | Tyco Electronics Corporation | Reflowable thermal fuse |
US8581686B2 (en) * | 2009-03-24 | 2013-11-12 | Tyco Electronics Corporation | Electrically activated surface mount thermal fuse |
US20100245022A1 (en) * | 2009-03-24 | 2010-09-30 | Tyco Electronics Corporation | Electrically activated surface mount thermal fuse |
US8854784B2 (en) | 2010-10-29 | 2014-10-07 | Tyco Electronics Corporation | Integrated FET and reflowable thermal fuse switch device |
US9240300B2 (en) * | 2010-12-31 | 2016-01-19 | Xiamen Set Electronics Co., Ltd | Device comprising a thermal fuse and a resistor |
US20130293343A1 (en) * | 2010-12-31 | 2013-11-07 | Xiamen Set Electronics Co., Ltd. | Device combining a thermal fuse and a resistor |
US20160099125A1 (en) * | 2012-12-05 | 2016-04-07 | Eaton Corporation | Fuse with carbon fiber fusible element |
US9805897B2 (en) * | 2012-12-05 | 2017-10-31 | Eaton Corporation | Fuse with carbon fiber fusible element |
US9324533B2 (en) | 2013-03-14 | 2016-04-26 | Mersen Usa Newburyport-Ma, Llc | Medium voltage controllable fuse |
US9490096B2 (en) | 2013-03-14 | 2016-11-08 | Mersen Usa Newburyport-Ma, Llc | Medium voltage controllable fuse |
US20160042904A1 (en) * | 2014-08-08 | 2016-02-11 | Tyco Electronics France Sas | Smart Fuse for Circuit Protection |
US9548177B2 (en) * | 2014-08-08 | 2017-01-17 | Littelfuse France Sas | Smart fuse for circuit protection |
WO2018136317A1 (en) * | 2017-01-17 | 2018-07-26 | Littelfuse, Inc. | Fuse with conical open coil fusible element |
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